Carabas, a senior mechanic at St. Denis who has been announcing the newspaper for a Bugatti car in the 27s for years, is contacted by young Raul proposing to buy this car. The two leave for Biarritz where thirty years before Carabas had lost the traces of Bugatti and the fascinating and enigmatic Countess Myriam du Terrail with whom she had had a loving adventure that had upset her. Carabas forces young Raul to follow the same itinerary along with the mysterious Countess: a journey full of obscure dangers and disturbing surprises for a risky mission to which the woman was forced by a blackmail. After having seduced her to get the covenant, the woman suddenly disappeared along with Bugatti leaving her an enigmatic message: the silver elephant that adorned the car's bonnet and that Carabas brought with it. In Biarritz the Bugatti that Raul's delivery is devoid of that ornament: not even now after thirty years Carabas can solve this rebus.